Implement in-memory repositories, XML load validation, and menu exit/list commands

- Add generic Repository<T> interface; EventRepository/UserRepository extend it
- Implement InMemoryEventRepository/InMemoryUserRepository backed by ArrayList
- Rename XMLLoader to XMLLoaderV1, add LoadValidator and mapper/v2 package
- Add OrderBookTradingMechanism
- Add User(String, int) convenience constructor
- Add ListEventsMenuCommand and ExitMenuCommand, isExit() on MenuCommand
- Menu now sizes selection range by max command index and exits on isExit()
- LoadFileMenuCommand reports validation issues on failed loads
- Untrack test-data/ and config.properties from .gitignore

13 files changed, 201 insertions, 53 deletions

diff --git a/service/src/main/java/market/guess/service/LocalGuessMarketContext.java b/service/src/main/java/market/guess/service/LocalGuessMarketContext.java
index 16ee1b8..19c7297 100644
--- a/service/src/main/java/market/guess/service/LocalGuessMarketContext.java
+++ b/service/src/main/java/market/guess/service/LocalGuessMarketContext.java
@@ -41,7 +41,7 @@ public final class LocalGuessMarketContext implements GuessMarketContext {
 
   @Override
   public List<EventSummaryDTO> listEvents() {
-    return eventRepository.getAllEvents().stream().map(Event::toEventSummary).toList();
+    return eventRepository.getAll().stream().map(Event::toEventSummary).toList();
   }
 
   @Override
@@ -58,9 +58,14 @@ public final class LocalGuessMarketContext implements GuessMarketContext {
   public PurchaseReceiptDTO buyShares(
       String userName, String eventKey, String optionKey, int quantity)
       throws GuessMarketException {
-    var event = eventRepository.getEvent(eventKey);
+    var optional = eventRepository.get(eventKey);
+
+    var userOptional = userRepository.get(userName);
+    if (optional.isEmpty() || userOptional.isEmpty()) throw new GuessMarketException();
+
+    var event = optional.get();
+    var user = userOptional.get();
     var option = event.getOption(optionKey);
-    var user = userRepository.getUser(userName);
     var trade = tradingOperation.buy(event, user, option, quantity);
     return new PurchaseReceiptDTO();
   }
diff --git a/service/src/main/java/market/guess/service/domain/Trade.java b/service/src/main/java/market/guess/service/domain/Trade.java
index cb6ed93..0c07749 100644
--- a/service/src/main/java/market/guess/service/domain/Trade.java
+++ b/service/src/main/java/market/guess/service/domain/Trade.java
@@ -4,12 +4,12 @@ import java.math.BigDecimal;
 import java.time.Instant;
 
 public record Trade(
-    long seq,
+    int id,
     Instant at,
     String userName,
     String optionKey,
     String optionName,
-    long quantity,
+    int uantity,
     BigDecimal sharesCost,
     BigDecimal commission) {
 
diff --git a/service/src/main/java/market/guess/service/domain/User.java b/service/src/main/java/market/guess/service/domain/User.java
index af9ac78..b2084b4 100644
--- a/service/src/main/java/market/guess/service/domain/User.java
+++ b/service/src/main/java/market/guess/service/domain/User.java
@@ -6,6 +6,10 @@ public final class User {
   private final String name;
   private final Account account;
 
+  public User(String name, int initialBalance) {
+    this(name, BigDecimalOptions.toMoney(initialBalance));
+  }
+
   public User(String name, BigDecimal initialBalance) {
     this.name = name;
     this.account = new Account(name, initialBalance);
diff --git a/service/src/main/java/market/guess/service/infrastructure/adapter/InstantTypeAdapter.java b/service/src/main/java/market/guess/service/infrastructure/adapter/InstantTypeAdapter.java
index 0e8a0e0..bc5ddb0 100644
--- a/service/src/main/java/market/guess/service/infrastructure/adapter/InstantTypeAdapter.java
+++ b/service/src/main/java/market/guess/service/infrastructure/adapter/InstantTypeAdapter.java
@@ -4,7 +4,8 @@ import com.google.gson.*;
 import java.lang.reflect.Type;
 import java.time.Instant;
 
-public class InstantTypeAdapter implements JsonSerializer<Instant>, JsonDeserializer<Instant> {
+public final class InstantTypeAdapter
+    implements JsonSerializer<Instant>, JsonDeserializer<Instant> {
   @Override
   public JsonElement serialize(Instant src, Type typeOfSrc, JsonSerializationContext context) {
     return new JsonPrimitive(src.toString());
diff --git a/service/src/main/java/market/guess/service/infrastructure/mapper/v2/EventMapperV2.java b/service/src/main/java/market/guess/service/infrastructure/mapper/v2/EventMapperV2.java
new file mode 100644
index 0000000..687ec33
--- /dev/null
+++ b/service/src/main/java/market/guess/service/infrastructure/mapper/v2/EventMapperV2.java
@@ -0,0 +1,66 @@
+package market.guess.service.infrastructure.mapper.v2;
+
+import java.util.ArrayList;
+import java.util.List;
+import market.guess.api.CommissionTiming;
+import market.guess.api.EventStatus;
+import market.guess.service.domain.Event;
+import market.guess.service.domain.Option;
+import market.guess.service.infrastructure.mapper.Mapper;
+import market.guess.service.mechanism.LmsrTradingMechanism;
+import market.guess.service.mechanism.OrderBookTradingMechanism;
+import market.guess.service.mechanism.TradingMechanism;
+import market.guess.service.model.v2.GMEvent;
+import market.guess.service.model.v2.GMLMSR;
+import market.guess.service.model.v2.GMOrderBook;
+
+public final class EventMapperV2 implements Mapper<GMEvent, Event> {
+
+  @Override
+  public Event toDomain(GMEvent source) {
+    return new Event(
+        getEventKey(source),
+        source.getId(),
+        source.getName(),
+        source.getDescription(),
+        source.getCommission().getValue(),
+        getTiming(source.getCommission().getType()),
+        getMechanism(source),
+        EventStatus.NOT_STARTED,
+        getOptions(source),
+        "");
+  }
+
+  private static String getEventKey(GMEvent event) {
+    return String.valueOf(event.getId());
+  }
+
+  private static CommissionTiming getTiming(String type) throws IllegalArgumentException {
+    return switch (type) {
+      case "on-close" -> CommissionTiming.ON_CLOSE;
+      case "on-purchase" -> CommissionTiming.ON_PURCHASE;
+      default -> throw new IllegalArgumentException("Unknown commission type: " + type);
+    };
+  }
+
+  private static TradingMechanism getMechanism(GMEvent source) {
+    if (source.getGMMethod().getGMLMSR() instanceof GMLMSR lmsr) {
+      return new LmsrTradingMechanism(lmsr.getB());
+    }
+    if (source.getGMMethod().getGMOrderBook() instanceof GMOrderBook orderBook) {
+      return new OrderBookTradingMechanism(
+          orderBook.getAllowMint().equalsIgnoreCase("true"),
+          orderBook.getInitial(),
+          orderBook.getD());
+    }
+    throw new IllegalArgumentException();
+  }
+
+  private static List<Option> getOptions(GMEvent x) {
+    var ret = new ArrayList<Option>(x.getGMOptions().getGMOption().size());
+    for (var i = 0; i < x.getGMOptions().getGMOption().size(); i++) {
+      ret.add(new Option(getEventKey(x) + ":" + i, x.getGMOptions().getGMOption().get(i)));
+    }
+    return ret;
+  }
+}
diff --git a/service/src/main/java/market/guess/service/infrastructure/provider/LoadValidator.java b/service/src/main/java/market/guess/service/infrastructure/provider/LoadValidator.java
new file mode 100644
index 0000000..c1c3895
--- /dev/null
+++ b/service/src/main/java/market/guess/service/infrastructure/provider/LoadValidator.java
@@ -0,0 +1,22 @@
+package market.guess.service.infrastructure.provider;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import market.guess.api.ProblemDTO;
+
+public final class LoadValidator {
+  private final List<ProblemDTO> problems = new ArrayList<>();
+
+  public void append(String code, String humanizedMessage, String location) {
+    problems.add(new ProblemDTO(code, humanizedMessage, location));
+  }
+
+  public boolean isValid() {
+    return problems.isEmpty();
+  }
+
+  public List<ProblemDTO> getIssues() {
+    return Collections.unmodifiableList(problems);
+  }
+}
diff --git a/service/src/main/java/market/guess/service/infrastructure/provider/v1/XMLLoader.java b/service/src/main/java/market/guess/service/infrastructure/provider/v1/XMLLoaderV1.java
index 9333350..7af22ea 100644
--- a/service/src/main/java/market/guess/service/infrastructure/provider/v1/XMLLoader.java
+++ b/service/src/main/java/market/guess/service/infrastructure/provider/v1/XMLLoaderV1.java
@@ -4,28 +4,24 @@ import jakarta.xml.bind.JAXBContext;
 import jakarta.xml.bind.JAXBException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.List;
 import market.guess.api.LoadResultDTO;
-import market.guess.service.domain.BigDecimalOptions;
-import market.guess.service.domain.Event;
-import market.guess.service.infrastructure.mapper.Mapper;
+import market.guess.service.domain.User;
+import market.guess.service.infrastructure.mapper.v1.EventMapperV1;
+import market.guess.service.infrastructure.provider.LoadValidator;
 import market.guess.service.infrastructure.provider.Loader;
-import market.guess.service.model.v1.GMEvent;
 import market.guess.service.model.v1.GuessMarket;
 import market.guess.service.repository.EventRepository;
 import market.guess.service.repository.UserRepository;
 
-public final class XMLLoader implements Loader {
+public final class XMLLoaderV1 implements Loader {
   private final JAXBContext context;
 
   private final EventRepository eventRepository;
   private final UserRepository userRepository;
-  private final Mapper<GMEvent, Event> mapper;
+  private final EventMapperV1 mapper;
 
-  public XMLLoader(
-      EventRepository eventRepository,
-      UserRepository userRepository,
-      Mapper<GMEvent, Event> mapper) {
+  public XMLLoaderV1(
+      EventRepository eventRepository, UserRepository userRepository, EventMapperV1 mapper) {
     super();
     this.eventRepository = eventRepository;
     this.userRepository = userRepository;
@@ -39,22 +35,27 @@ public final class XMLLoader implements Loader {
 
   @Override
   public LoadResultDTO load(Path path) {
+    var validator = new LoadValidator();
+    if (path.getFileName() == null
+        || !path.getFileName().toString().toLowerCase().endsWith(".xml")) {
+      validator.append("NOT_XML", "The file must be an XML.", path.toString());
+    }
 
     try (var stream = Files.newInputStream(path)) {
 
       var doc = (GuessMarket) context.createUnmarshaller().unmarshal(stream);
 
       for (var event : doc.getGMEvents().getGMEvent()) {
-        eventRepository.addEvent(mapper.toDomain(event));
+        eventRepository.add(mapper.toDomain(event));
       }
 
-      userRepository.addUser("Tester", BigDecimalOptions.toMoney(9_999_999));
+      userRepository.add(new User("Tester", 9_999_999));
 
-      return LoadResultDTO.success("udk", 1);
+      return LoadResultDTO.success(path.toString(), eventRepository.getAll().size());
     } catch (Exception e) {
-
+      validator.append("UNREADABLE", "The file could not be read.", path.toString());
     }
 
-    return LoadResultDTO.failure(path.toFile().getName(), List.of());
+    return LoadResultDTO.failure(path.toString(), validator.getIssues());
   }
 }
diff --git a/service/src/main/java/market/guess/service/mechanism/OrderBookTradingMechanism.java b/service/src/main/java/market/guess/service/mechanism/OrderBookTradingMechanism.java
new file mode 100644
index 0000000..62feb02
--- /dev/null
+++ b/service/src/main/java/market/guess/service/mechanism/OrderBookTradingMechanism.java
@@ -0,0 +1,40 @@
+package market.guess.service.mechanism;
+
+import java.math.BigDecimal;
+import market.guess.api.MechanismType;
+
+public final class OrderBookTradingMechanism implements TradingMechanism {
+  private final boolean allowMint;
+  private final int initial;
+  private final int d;
+
+  public OrderBookTradingMechanism(boolean allowMint, int initial, int d) {
+    super();
+    this.allowMint = allowMint;
+    this.initial = initial;
+    this.d = d;
+  }
+
+  @Override
+  public MechanismType type() {
+    return MechanismType.ORDER_BOOK;
+  }
+
+  @Override
+  public BigDecimal openingCost(int optionCount) {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'openingCost'");
+  }
+
+  @Override
+  public BigDecimal costOfBuying(long[] q, int optionIndex, long quantity) {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'costOfBuying'");
+  }
+
+  @Override
+  public double[] prices(long[] q) {
+    // TODO Auto-generated method stub
+    throw new UnsupportedOperationException("Unimplemented method 'prices'");
+  }
+}
diff --git a/service/src/main/java/market/guess/service/repository/EventRepository.java b/service/src/main/java/market/guess/service/repository/EventRepository.java
index 94999cb..afc5371 100644
--- a/service/src/main/java/market/guess/service/repository/EventRepository.java
+++ b/service/src/main/java/market/guess/service/repository/EventRepository.java
@@ -1,12 +1,5 @@
 package market.guess.service.repository;
 
-import java.util.List;
 import market.guess.service.domain.Event;
 
-public interface EventRepository {
-  Event getEvent(String id);
-
-  List<Event> getAllEvents();
-
-  void addEvent(Event event);
-}
+public interface EventRepository extends Repository<Event> {}
diff --git a/service/src/main/java/market/guess/service/repository/InMemoryEventRepository.java b/service/src/main/java/market/guess/service/repository/InMemoryEventRepository.java
index 81eba74..eb7763e 100644
--- a/service/src/main/java/market/guess/service/repository/InMemoryEventRepository.java
+++ b/service/src/main/java/market/guess/service/repository/InMemoryEventRepository.java
@@ -1,25 +1,27 @@
 package market.guess.service.repository;
 
+import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
+import java.util.Optional;
 import market.guess.service.domain.Event;
 
 public final class InMemoryEventRepository implements EventRepository {
+  private final List<Event> events = new ArrayList<>();
 
   @Override
-  public Event getEvent(String id) {
-    // TODO Auto-generated method stub
-    throw new UnsupportedOperationException("Unimplemented method 'getEvent'");
+  public Event add(Event element) {
+    events.add(element);
+    return element;
   }
 
   @Override
-  public List<Event> getAllEvents() {
-    // TODO Auto-generated method stub
-    throw new UnsupportedOperationException("Unimplemented method 'getAllEvents'");
+  public Optional<Event> get(String id) {
+    return events.stream().filter(event -> event.getEventKey().equalsIgnoreCase(id)).findFirst();
   }
 
   @Override
-  public void addEvent(Event event) {
-    // TODO Auto-generated method stub
-    throw new UnsupportedOperationException("Unimplemented method 'addEvent'");
+  public List<Event> getAll() {
+    return Collections.unmodifiableList(events);
   }
 }
diff --git a/service/src/main/java/market/guess/service/repository/InMemoryUserRepository.java b/service/src/main/java/market/guess/service/repository/InMemoryUserRepository.java
index 951dea8..0b5cfe7 100644
--- a/service/src/main/java/market/guess/service/repository/InMemoryUserRepository.java
+++ b/service/src/main/java/market/guess/service/repository/InMemoryUserRepository.java
@@ -1,19 +1,27 @@
 package market.guess.service.repository;
 
-import java.math.BigDecimal;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.Optional;
 import market.guess.service.domain.User;
 
 public final class InMemoryUserRepository implements UserRepository {
+  private final List<User> users = new ArrayList<>();
 
   @Override
-  public User getUser(String name) {
-    // TODO Auto-generated method stub
-    throw new UnsupportedOperationException("Unimplemented method 'getUser'");
+  public User add(User element) {
+    users.add(element);
+    return element;
   }
 
   @Override
-  public void addUser(String name, BigDecimal initialBalance) {
-    // TODO Auto-generated method stub
-    throw new UnsupportedOperationException("Unimplemented method 'addUser'");
+  public Optional<User> get(String id) {
+    return users.stream().filter(u -> u.getName().equalsIgnoreCase(id)).findFirst();
+  }
+
+  @Override
+  public List<User> getAll() {
+    return Collections.unmodifiableList(users);
   }
 }
diff --git a/service/src/main/java/market/guess/service/repository/Repository.java b/service/src/main/java/market/guess/service/repository/Repository.java
new file mode 100644
index 0000000..8ea1817
--- /dev/null
+++ b/service/src/main/java/market/guess/service/repository/Repository.java
@@ -0,0 +1,12 @@
+package market.guess.service.repository;
+
+import java.util.List;
+import java.util.Optional;
+
+public interface Repository<T> {
+  T add(T element);
+
+  Optional<T> get(String id);
+
+  List<T> getAll();
+}
diff --git a/service/src/main/java/market/guess/service/repository/UserRepository.java b/service/src/main/java/market/guess/service/repository/UserRepository.java
index 78d620d..86cc9a6 100644
--- a/service/src/main/java/market/guess/service/repository/UserRepository.java
+++ b/service/src/main/java/market/guess/service/repository/UserRepository.java
@@ -1,11 +1,5 @@
 package market.guess.service.repository;
 
-import java.math.BigDecimal;
 import market.guess.service.domain.User;
 
-public interface UserRepository {
-
-  User getUser(String name);
-
-  void addUser(String name, BigDecimal initialBalance);
-}
+public interface UserRepository extends Repository<User> {}